Cranberry Twp is on 472.2375 PL 127.3. Units #42-, and #43-. Cranberry Fire And EMS is Dispatched on 472.0875 PL 103.5 Fire Station 21, EMS Station 51.
Butler County has gone to a UHF system, that is neither trunked or digigital. The Pro-97 will receive them quite well, at least mine does. They have just swithched to this system in the past 1-2 years, so I would think its unlikely they will be switching to a trunked system soon.
I'm not sure what the database has in it, but Butler uses :
472.2375 PL 127.3 - Police Ch. 1
471.500 PL 131.8 - Police Ch. 2
472.0875 PL 103.5 - Fire And EMS Dispatch
470.350 PL 107.2 - Fire Response 2
471.175 PL 110.9 - Fire Response 3
472.5125 PL 114.8 - EMS Response 4
Frank K3FSS